Air quality response in China linked to the 2019 novel Coronavirus (COVID-19) mitigation

Efforts to stem the spread of COVID-19 in China hinged on severe restrictionsto human movement starting January 23rd, 2020 in Wuhan and subsequentlyto other provinces. Here, we quantify the ancillary impacts on air pollutionand human health using inverse emissions estimates based on multiple satellite observations. NOx and SO2 emission reductions increased surface ozoneby up to 16 ppb over northern China but decreased PM2.5 by up to 23 µg m−3nationwide. Air pollution appears to have substantially offset hospital admissions related to COVID-19, augmenting mitigation efforts, such as in the Hubeiprovince with ∼400 reduced admissions. Changes in human exposure are as1sociated with about 2,100 increased ozone-related morbidity incidences andavoidance of at least 60,000 PM2.5-related morbidity incidences.